Physics Helpp?

[Jennifer T]

Matt forgot to put the fabric softener in the wash. As his socks tumbled in the dryer, they became charged. If a small piece of lint with a charge of +1.25 E -19 C is attracted to the socks by a force of 3.0 E -9 N, what is the magnitude of the electric field at this location?

Suppose an electric field with a magnitude of 2.8 E 4 N/C at a certain location, points due south. If a charge of -4.0 E -6 C is brought to the location, what is the electrostatic force that acts on this charge?

Think back to Coulomb's Law. Two coins with identical charges are placed on a lab table 1.35 m apart.

If each coin experiences a force of 2.0 N because of the presence of the other coin, calculate the charge on each coin.

Would the force be classified as a force of attraction or repulsion

[Murtaza]

F = KQq/r²
3x10^-9 = (8.99x10^9)(Q)(1.25x10^-19)/(r²)
Q/r² = (2400/899)

Electric Field Strength = kQ/r²
E = (8.99x10^9)((2400/899))
E = 2.4x10^10 NC^-1

2.8x10^4 = k(Q)/r²

F = k(Q)q/r²
F = (2.8x10^4)(4x10^-6)
F = 0.112 N

F = kQQ/r²
2 = (8.99x10^9)Q²/(1.35)²
Q = 2.013580146x10^-5 N

Force is attraction .